Comparison of 25 G and 29 G Quincke spinal needles in paediatric day case surgery. A prospective randomized study of the puncture characteristics, success rate and postoperative complaints.

A comparison of a 25 G with a 29 G Quincke needle was performed in paediatric day case surgery. Sixty healthy children aged 1 year to 13 years were randomly allocated to have spinal anaesthesia with either 25 G or 29 G Quincke needle without an introducer needle. There was a failure rate of 10% with the 29 G spinal needle compared with 0% with the 25 G needle. The time needed to perform dural puncture was shorter using 25 G than 29 G needle, 22 (+/- 31)(SD) vs 59 (+/- 63) s. The time taken for cerebrospinal fluid to appear at the needle hub was also longer, 4 (+/- 3) vs 8 (+/- 5) s. The number of puncture attempts was similar, 1.2 (+/- 0.6) vs 1.4 (+/- 0.8), with 25 G and 29 G needle. Low back pain, 5 vs1, and nonpositional headache, 2 vs 4, after 25 G and 29 G needles, respectively, were the most frequent postoperative complaints. Mild postdural puncture headache occurred in one eight year old male patient in the 25 G group. In conclusion, lumbar puncture without introducer needle was possible with both needles. The puncture characteristics favoured the 25 G needle. A shorter needle could partly alleviate the difficulties with the 29 G needle.